The distribution of rare earth elements (REEs) in nuclear ore samples provided basic and important information for nuclear forensics. A method was developed for the determination of REEs in uranium ore samples by triple quadrupole inductively coupled plasma mass spectrometry (ICP-MS/MS). A simple and reliable chemical procedure was established for the separation of REEs from the uranium matrix before the measurement. Oxygen was introduced into the mass spectrometry equipment as the reaction gas and the formed REE oxides were detected with the mass-shift strategy. The influences of polyatomic interferents on the measurement of REEs, especially the influences of light REE oxides on the measurement of heavy REEs, were significantly suppressed. The method detection limits were below 1 pg mL⁻¹ for all REEs, ensuring the precise and accurate measurement of REEs in small amounts of uranium ore samples. Several geological reference materials were measured for method validation and the obtained results were consistent with the reported values. Finally, the concentrations of REEs in six types of uranium ore sample were determined. The distribution patterns of REEs in the same type of uranium ore sample were consistent, while those of REEs in different types of uranium ore sample varied significantly. The results further suggested that REE distribution patterns could be used as fingerprints for source identification of related nuclear materials.

中文翻译：

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三重四极杆电感耦合等离子体质谱法测定铀矿样品中的痕量稀土元素

核矿石样品中稀土元素（REEs）的分布为核取证提供了基础和重要的信息。开发了一种通过三重四极杆电感耦合等离子体质谱 (ICP-MS/MS) 测定铀矿石样品中 REE 的方法。建立了一种简单可靠的化学程序，用于在测量前从铀基质中分离 REE。将氧气作为反应气体引入质谱设备，并使用质量转移策略检测形成的 REE 氧化物。多原子干扰物对稀土元素测量的影响，特别是轻稀土氧化物对重稀土元素测量的影响得到显着抑制。方法检测限低于 1 pg mL ^-1适用于所有 REE，确保对少量铀矿样品中的 REE 进行精确测量。测量了几种地质参考物质用于方法验证，所得结果与报告值一致。最后，测定了六种铀矿石样品中稀土元素的浓度。同类型铀矿样品中稀土元素的分布规律是一致的，而不同类型铀矿样品中稀土元素的分布规律存在显着差异。结果进一步表明，REE 分布模式可用作相关核材料来源识别的指纹。